Martians vs Humans

[Finn N. Rasmussen]

Don McAllister wrote:
--<snip>-----
On the other hand if gene flow was practically zero and if there were
differential selective forces or significant genetic drift, then
apomorphies might well develop and one could start talking about a new
Martian species.
-->endsnip>--

Why isn't it the terrrestrial humans that constitute the new species? If
you apply the biological species concept both are  species, even if they
are practically indistinguishable. Cladistically, both species are
different form the original H. sapiens, as they now constitute two
different lines of evolution that can aquire new attributes
independently. Under the traditional mophological-typological species
concept we may observe two, three or just one species depending on
wether the Martians, the Terrestrials, both or none develop new
characters. And it is not necessarily the Martians that will change -
they are probably too few to spoil their environment the first million
years.

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Finn N Rasmussen
Botanical Institute, University of Copenhagen